RU128948U1 - DEVICE FOR MONITORING THE ELECTRIC NETWORK PARAMETERS AND PROTECTING FROM OVERVOLTAGE OF ELECTRICAL EQUIPMENT - Google Patents

Abstract

1. A device for monitoring the parameters of the electrical network and overvoltage protection of electrical equipment, comprising a three-phase network made of high voltage, a non-linear surge suppressor, fuses, a step-down three-phase transformer, a power circuit breaker made of electromagnetic relays and varistors, a multi-function power management device equipped with contactors, made by high-speed and electromagnetic, power bus made three-wire and which serves to at least one load, moreover, from the input side of the segment of the three-phase network, a non-linear - three-wire overvoltage limiter is connected to it, fuses are connected to its inputs, the outputs of which are connected to the inputs of the step-down three-phase transformer, the outputs of which are connected in series to the inputs of the electromagnetic relays of the power automaton, the outputs of which are installed and connected in parallel to the varistors of the power automaton, sequentially to the outputs of the electromagnetic relays of the power automaton and the inputs of the contactors of the multifunction power management device are connected, and the outputs of the contactors are respectively connected to the power bus. 2. The device according to claim 1, characterized in that a three-pole disconnector is introduced, and the device is equipped with an additional non-linear surge suppressor, additional fuses, an additional step-down three-phase transformer, an additional power automaton made of electromagnetic relays and varistors, a multifunctional electronic control device

Description

The utility model relates to electrical engineering and can be used to protect various electrical objects during their power supply, mainly to protect the equipment of the block boxes of the control point and control the linear part of the pipeline from overvoltage.

There are various technical solutions that provide remote monitoring of the functioning of electrical equipment.

Patent RU, 2339046 (published November 20, 2008; IPC G01R 11/32) describes a device for monitoring electric energy signals, comprising an electric line interface for measuring electric line signals, a non-volatile storage medium, and a processor configured to record into a non-volatile storage medium for displaying information about the waveform of the measured electrical line signals continuously and regardless of whether an anomaly has been identified.

Patent RU 22268 (published March 10, 2002; IPC H01J 13/00) describes a distribution power supply and / or information-measuring network with transmission over the power grid. The network includes energy consumption meters, meter controllers connected by a cable to the indicated meters, a data collection device connected to the controllers of these meters by one of the phase wires and the neutral wire of the main power supply network. The controller of these counters is made in the form of a series-connected interface module, a processor unit and a power supply modem connected through one of the three phase wires and a neutral wire of the main power supply network with a data collection device configured to transmit data to the central control room.

The closest to the proposed technical solution is included in its composition multifunctional device for power management "ELTEK" OFT. 18.1337.00.00.00, TU 4217-1337-20885897-20011, which provides measurement and storage of information on the parameters of the power supply network in non-volatile memory, as well as automatic input of the reserve in accordance with the circuit connected to the three inputs of the three-phase voltage.

ELTEK includes the following functional elements:

- processor module (MP),

- display and control module (MIU),

- input-output module (MVV),

- voltage sensor module (MDN),

- power source (IP),

- information module (IM),

- EMC filter.

ELTEK is equipped with contactors KM1, KM2, KM3, made by high-speed and electromagnetic. MP provides the implementation of all the functions of ELTEK based on internal software. MIU provides an indication of the current operating mode, device parameters, alarms, as well as entering settings, viewing the defect log via navigation buttons and issuing operator control commands. MVV communicates with upper-level control systems and is designed to control ELTEK via discrete inputs and RS-485 interface, as well as to signal the status and operation modes of ELTEK using discrete outputs and RS-485 interface. MDN with transformer type voltage sensors measures the line voltage for three inputs with the required accuracy over the entire range of the measured voltage. The UPS provides a stable power supply to the functional elements of ELTEK. The MI provides recording of events: pulse overvoltage on all inputs, temporary overvoltages, undervoltage, switching on and off of input contactors, turning off the second backup input using a trip unit, ELTEK protection settings, emergency input switching situations. This data can be used to determine the causes of equipment failure. ELTEK provides the transfer of IM data to a personal computer via USB with a data transfer rate of at least 57600 bps. To ensure filtering of electrical noise in the ELTEK power supply circuit that occurs when switching controlled coils of electromagnetic contactors, the ELTEK includes an EMC filter (electromagnetic compatibility )

The main limitation of this device is the inability to control the parameters of the high-voltage three-phase network ~ 10 kV (ELTEK is designed to work with the network up to 0.4 kV, 50 Hz).

The task solved by the utility model is the improvement of technical and operational characteristics.

The technical result that was obtained by performing the claimed utility model is to increase the reliability of protection of electrical equipment from high voltage overvoltage, to ensure and improve control of the main parameters of the electric high voltage network.

To solve the problem with the achievement of the specified technical result, the device for monitoring the parameters of the electrical network and overvoltage protection of electrical equipment contains a three-phase network made of high voltage, a non-linear surge suppressor, fuses, a step-down three-phase transformer, a power automat made of electromagnetic relays and varistors, a multifunction device power management, equipped with contactors made by high-speed and electronic magnetic, a three-wire power bus that serves to connect at least one load, and from the input side of a three-phase network segment a non-linear surge suppressor is connected to it, a three-wire circuit, to the inputs of which fuses are connected, the outputs of which are connected to the inputs of a step-down three-phase transformer, the outputs of which are serially connected to the inputs of the electromagnetic relays of the power automaton, the outputs of which are variably installed and connected th automaton sequentially to the outputs of the electromagnetic relay of the power machine inputs connected contactors multifunctional power management device, and outputs respectively connected to the contactor power bus.

Additional embodiments of the device are possible, in which it is advisable that:

- a three-pole disconnector was introduced, and the device was equipped with an additional non-linear surge suppressor, additional fuses, an additional step-down three-phase transformer, an additional power circuit breaker made of electromagnetic relays and varistors, a multi-function power management device equipped with additional contactors, and from the output side of the three-phase network to it is connected an additional surge suppressor non-linear, to the inputs of the cat additional fuses are connected, the outputs of which are connected to the inputs of the additional step-down three-phase transformer, the outputs of which are connected in series to the inputs of the electromagnetic relays of the additional power automaton, the outputs of which are installed and connected to the varistors of the additional power automaton, and the inputs of additional multifunction device contactors controlled I power, and outputs additional contactors respectively connected to the power bus, wherein the three-pole disconnector connected between the input and output of three-phase network segment;

- a load protection circuit breaker was introduced, made on the basis of series-connected magnetic and thermal releases, and the load is connected to the power bus through a load protection circuit breaker;

- the power bus was made common or partitioned.

The indicated advantages of the utility model, as well as its features are explained using the best option for its implementation with reference to the accompanying drawings.

Figure 1 depicts a functional diagram of the claimed device;

Figure 2 is a functional diagram of a multifunctional power management device included in the device of figure 1.

A device for monitoring the parameters of the electrical network and overvoltage protection of electrical equipment (Fig. 1) contains a three-phase network 1: A, B, C, made high-voltage, non-linear surge arrestor 2, surge arresters 3, step-down three-phase transformer 4 (PTT), a power switch 5 made of electromagnetic relays 6 and varistors 7, a multi-function device 8 power management (ELTEK), equipped with contactors 9 made of high-speed and electromagnetic, the power bus 10: s, b, a, made three-wire and which serves to connect at least one load 11 (M). From the input side of the segment of the three-phase network 1, an arrester 2 is connected to it (in parallel) - three-wire. The fuses 3 are connected to the inputs of the arrester 2, the outputs of which are connected to the inputs of a step-down three-phase transformer 4. The outputs of the PTT 4 are connected in series to the inputs of the electromagnetic relays 6 of the power automat 5. The outputs of the electromagnetic relays 6 are connected in parallel to the varistors 7 of the power automat 5. In series to the outputs of the electromagnetic relays 6 power automaton 5 connected to the inputs of the contactors 9 ELTEK 8. The outputs of the contactors 9 are respectively connected to the power bus 10.

To further increase reliability, a redundant circuit can be introduced into the circuit, similar to the circuit described above. The device is equipped with an additional arrester 12, additional fuses 13, additional PTT 14, additional power circuit breaker 15 made of electromagnetic relays 6 and varistors 7. ELTEK 8 is equipped with additional contactors 19. From the output side of section 1 of the three-phase network, an additional arrester is connected to it (in parallel) 12, to the inputs of which additional fuses are connected 13. The outputs of the fuses 13 are connected to the inputs of the additional PTT 14. The outputs of the PTT 14 are connected in series to the electromagnetic inputs relay 6 of the additional power automaton 15. Beyond the outputs of the electromagnetic relay 6 of the additional power automaton 15, varistors 7 of the additional power automaton 15 are connected in parallel. The outputs of the additional contactors 19 of ELTEK 8 are connected in series with the outputs of the electromagnetic relays 6 of the additional power automaton 8. The outputs of the additional contactors 19 are respectively connected to power bus 10. A three-pole disconnector 20. A three-pole disconnector 20 is connected between the input and output of the tr hfaznoy network 1.

To further increase the reliability of protection, a load protection device 21 may be introduced into the device based on series-connected magnetic trip units 22 and heat spreaders 23, and the load is connected to the power bus 1 through the load protection device 21.

The power bus 10 can be made in the form of a common power bus (figure 1) or partitioned (not shown in figure 1).

The device operates (figure 1) as follows.

When implementing power supply projects for various facilities in underdeveloped areas of the country, organizations often encounter the impossibility of uninterrupted and high-quality power supply for their equipment. Due to the low population density of the country, the state of electric grid facilities in some regions is in unsatisfactory condition, which significantly affects the quality of electricity supplied. In order to avoid serious financial losses due to the failure of expensive equipment or the loss of important information, the following device was developed to control the parameters of the electrical network and protect against overvoltage of electrical equipment. To protect electrical equipment from lightning discharges on the 10 kV side, a non-linear overvoltage limiter 2 is used (for example, OPN-10, where the number 10 indicates a nominal voltage of 10 kV. It is connected by its three inputs from the input side of a segment of a three-phase network 1 to it , respectively, and its three outputs are free (not connected to a three-phase network 12). The arrester 2 has a non-linear characteristic of internal resistance, when the voltage rises above the nominal value (12.5 kV is accepted for arrester 10), the intrinsic (internal) resistance of the arrester 2 starts decrease nonlinearly, thereby dumping the excess power of a lightning discharge into the ground and partially dissipating it in its conductive parts, while keeping in mind that when lightning strikes directly into a three-phase network 1 or when it is struck in the immediate vicinity m electrical equipment (e.g., a block box item for monitoring and control of the linear part of the pipeline), a private dissipation ability arrester 2 may be insufficient and it will be damaged. It should also be noted that individual lightning discharges have sufficient power to have a negative effect on all subsequent equipment with a triggered arrester 2 for a certain time. In order to avoid damage to electrical equipment by lightning impulses, as well as to protect the line from short circuit, fuses 3 (fuses) are installed between the inputs of the arrester 2 and the inputs of a step-down three-phase transformer 4.

In the event of insignificant voltage surges that are not monitored by the arrester 2 and fuses 3, a power automat 5 is installed in the power line at the output of the step-down three-phase circuit breaker 4 (from 10 kV to 0.4 kV), made of electromagnetic relays 6 and varistors 7. The outputs of the step-down three-phase circuit breaker 4 are connected in series to the inputs of electromagnetic relays 6 of the circuit breaker 5, the outputs of which are connected and connected in parallel to the varistors 7 of the circuit breaker 5. Varistor 7 (eng. vari (able) (resi) stor - variable resistor) - semiconductor a resistor whose electrical resistance (conductivity) depends non-linearly on the applied voltage, that is, having a non-linear symmetrical current-voltage characteristic and having two terminals. The inputs of the varistors 7 are connected to the outputs of the electromagnetic relay 6, and the free (not connected to the line) conclusions are grounded. Due to the absence of accompanying currents during an abrupt change in the applied voltage, the varistors 7 are the main element for the production of surge protection devices (SPD). The varistors 7 carry out the dissipation of excess power of pulses of a lower voltage class than the arrester 2. In case of overvoltage, the varistors 7 perform two functions: dissipate the excess power and provide the development of electromagnetic relays 6 (opening their contacts) of the power automaton 5, the parameters of the contact opening current are determined experimentally, in Dependence of the type (brand) of the selected electromagnetic relay 6 and the type (brand) of varistors 7.

After the varistors 7 to the outputs of the electromagnetic relays 6 of the power automaton 5 are connected the inputs of the contactors 9 ELTEK 8, which are part of it. ELTEK 8 is connected to the line (three-wire) in accordance with the Operating Manual of the OFT. 18.1337.00.00.00 and figure 2, and also performs all the functions specified in the Guide. The outputs of the contactors 9 are respectively connected to the power bus 10.

The principle of operation of the ELTEK 8 device is based on monitoring the parameters of the 0.4 kV network. If there are any deviations (overvoltage, voltage loss, change in the voltage frequency, change in the asymmetry coefficient, exceeding the control of the number of switching cycles, change in the state of contactors 9, etc.) of the network parameters from program settings, the device disconnects the contactors 9 and de-energizes the electrical equipment . When the network parameters return to normal, the device turns on the contactors 9 and energizes the equipment (for example, the electrical equipment of the block boxes). ELTEK 8 is connected to a computer via a USB interface to display operating parameters and read the event log. ELTEK 8 has its own power supply, protecting it from possible failure if the input voltage parameters deviate.

To further increase the reliability of protection, a redundant circuit can be introduced into the device (Fig. 1), made similar to the circuit described above, and operates similarly. This circuit is connected from the output side of the segment 1 of the three-phase network relative to ELTEK 8. The device is equipped with an additional arrester 12, additional fuses 13, additional PTT 14, additional power circuit breaker 15, additional contactors 19. A three-pole disconnector 20 is introduced into the device. A three-pole disconnector 20 is connected between the input and the output of a segment of a three-phase network 1.

For example, since the block boxes of the monitoring and control point of the linear part of the pipeline are powered by the second category of power supply, in the event of a break in the line from one side of the block box, the latter will be powered from another source of power supply. Also, in the event of failure of any element of the main power supply circuit, the block box will go from the main input to the input of the reserve (Emergency input of the reserve is organized through ELTEK 8, figure 2).

The three-pole disconnector 20 is designed to disconnect and turn on certain sections of the network or equipment that are energized, as well as to create a visible break in the electrical circuit when personnel work on the line or equipment. Three-pole disconnectors 20 can be made with three bushing insulators on which movable knives are mounted. Disconnectors of this type for a voltage of 10 kV and a rated current of 400 A indicate RVF-10/400, and with grounding knives RVFZ-10/400.

To further increase the reliability of protection in the device (Fig. 1), an automatic load protection device M may be introduced 21, made on the basis of series-connected magnetic releases 22 and thermal releases 23, and the load M is connected to the power bus 1 through the automatic load protection device 21.

The thermal release 23 is a bimetallic plate heated by a flowing current. When the current flows above the permissible value, the bimetallic plate bends and activates the trip mechanism. The response time depends on the current and can vary from seconds to an hour. The minimum current at which the thermal release must trip is 1.45 of the rated current of the fuse. Unlike the fuse, the circuit breaker is ready for the next use after cooling the plate.

Magnetic release 22 is a solenoid, the movable core of which can also actuate the release mechanism. The current passing through the switch flows through the coil of the solenoid and causes the core to retract when the specified threshold is exceeded. The instantaneous release, unlike the thermal one, works very quickly (fractions of a second), but with a much greater excess of current: 2 ÷ 10 times the nominal value, depending on its type.

The claimed device can be used both for power supply circuits with a common power bus (figure 1), and in the case of bus sections.

The main feature of the functioning of the claimed device is the remote monitoring of voltage quality indicators, which boils down to the use of existing telemechanics system tools together with the described device for collecting and processing data on the supply voltage parameters of a 10 kV high-voltage line, as well as block boxes of the control and monitoring point on the side 0 , 4 kV. Via the Modbus interface, through the LTM controller, you can obtain detailed data on the parameters of the mains, both on-line and off-line by reading the event log. Based on the data obtained, it is possible to judge the quality of the supplied electricity from one or another supplier and decide on the need to switch the section of the three-phase network 1 (10 kV) to another source of electricity.

The most successfully claimed device for monitoring the parameters of the electric network and overvoltage protection of electrical equipment is industrially applicable for protecting various electrical objects during their power supply, mainly for protecting the equipment of the block boxes of the control point and controlling the linear part of the pipeline from overvoltage.

Claims (4)

1. A device for monitoring the parameters of the electrical network and overvoltage protection of electrical equipment, comprising a three-phase network made of high voltage, a non-linear surge suppressor, fuses, a step-down three-phase transformer, a power circuit breaker made of electromagnetic relays and varistors, a multi-function power management device equipped with contactors, made by high-speed and electromagnetic, power bus made three-wire and which serves to at least one load, moreover, from the input side of the segment of the three-phase network, a non-linear - three-wire overvoltage limiter is connected to it, fuses are connected to its inputs, the outputs of which are connected to the inputs of the step-down three-phase transformer, the outputs of which are connected in series to the inputs of the electromagnetic relays of the power automaton, the outputs of which are installed and connected in parallel to the varistors of the power automaton, sequentially to the outputs of the electromagnetic relays of the power automaton and the inputs of the contactors of the multifunction power management device are connected, and the outputs of the contactors are respectively connected to the power bus. 2. The device according to claim 1, characterized in that a three-pole disconnector is introduced, and the device is equipped with an additional non-linear surge suppressor, additional fuses, an additional step-down three-phase transformer, an additional power automaton made of electromagnetic relays and varistors, a multifunctional power management device equipped with additional contactors moreover, from the output side of the three-phase network segment, an additional surge suppressor is connected to it non-linear, to the inputs of which additional fuses are connected, the outputs of which are connected to the inputs of an additional step-down three-phase transformer, the outputs of which are connected in series to the inputs of the electromagnetic relays of the additional power automaton, the outputs of which are varistors of the additional power automaton installed and connected in parallel, in series to the outputs of the electromagnetic relays of the additional power automaton connected inputs of additional contactors multifunction power control device, and the outputs of the additional contactors are respectively connected to the power bus, while a three-pole disconnector is connected between the input and output of the segment of the three-phase network. 3. The device according to claim 1, characterized in that a load protection circuit breaker is introduced, made on the basis of series-connected magnetic and thermal releases, and the load is connected to the power bus through a load protection circuit breaker. 4. The device according to claim 1, characterized in that the power bus is made common or partitioned.

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